Ante-Nicene Fathers, Vol III:
Tertullian: Part II: The Success of the Apostles, and Their Sufferings in the Cause of the Gospel, Foretold.

Chapter XXII.—The Success of the Apostles, and Their Sufferings in the Cause of the Gospel, Foretold.

You have the work of the apostles also predicted: “How beautiful are the feet of them which preach the gospel of peace, which bring good tidings of good,” 3400
not of war nor evil tidings. In response to which is the psalm, “Their sound is gone through all the earth, and their words to the ends of the world;” 3401
that is, the words of them who carry round about the law that proceeded from Sion and the Lords word from Jerusalem, in order that that might come to pass which was written: “They who were far from my righteousness, have come near to my righteousness and truth.” 3402
When the apostles girded their loins for this business, they renounced the elders and rulers and priests of the Jews. Well, says he, but was it not above all things that they might preach the other god? Rather 3403
(that they might preach) that very self-same God, whose scripture they were with all their might fulfilling! “Depart ye, depart ye,” exclaims Isaiah; “go ye out from thence, and touch not the unclean thing,” that is blasphemy against Christ; “Go ye out of the midst of her,” even of the synagogue. “Be ye separate who bear the vessels of the Lord.” 3404
For already had the Lord, according to the preceding words (of the prophet), revealed His Holy One with His arm, that is to say, Christ by His mighty power, in the eyes of the nations, so that all the 3405
nations and the utmost parts of the earth have seen the salvation, which was from God. By thus departing from Judaism itself, when they exchanged the obligations and burdens of the law for the liberty of the gospel, they were fulfilling the psalm, “Let us burst their bonds asunder, and cast away their yoke from us;” and this indeed (they did) after that “the heathen raged, and the people imagined vain devices;” after that “the kings of the earth set themselves, and the rulers took their counsel together against the Lord, and against His Christ.” 3406
What did the apostles thereupon suffer? You answer: Every sort of iniquitous persecutions, from men that belonged indeed to that Creator who was the adversary of Him whom they were preaching. Then why does the Creator, if an adversary of Christ, not only predict that the apostles should incur this suffering, but even express His displeasure 3407
thereat? For He ought neither to predict the course of the other god, whom, as you contend, He knew not, nor to have expressed displeasure at that which He had taken care to bring about. “See how the righteous perisheth, and no man layeth it to heart; and how merciful men are taken away, and no man considereth. For the righteous man has been removed from the evil person.” 3408
Who is this but Christ? “Come, say they, let us take away the righteous, because He is not for our turn, (and He is clean contrary to our doings).” 3409
Premising, therefore, and likewise subjoining the fact that Christ suffered, He foretold that His just ones should suffer equally with Him—both the apostles and all the faithful in succession; and He signed them with that very seal of which Ezekiel spake: “The Lord said unto me, Go through the gate, through the midst of Jerusalem, and set the mark Tau upon the foreheads of the men.” 3410
Now the Greek letter Tau and our own letter T is the very form of the cross, which He predicted would be the sign on our p. 341foreheads in the true Catholic Jerusalem, 3411
in which, according to the twenty-first Psalm, the brethren of Christ or children of God would ascribe glory to God the Father, in the person of Christ Himself addressing His Father; “I will declare Thy name unto my brethren; in the midst of the congregation will I sing praise unto Thee.” For that which had to come to pass in our day in His name, and by His Spirit, He rightly foretold would be of Him. And a little afterwards He says: “My praise shall be of Thee in the great congregation.” 3412
In the sixty-seventh Psalm He says again: “In the congregations bless ye the Lord God.” 3413
So that with this agrees also the prophecy of Malachi: “I have no pleasure in you, saith the Lord; neither will I accept your offerings: for from the rising of the sun, even unto the going down of the same, my name shall be great among the Gentiles; and in every place sacrifice shall be offered unto my name, and a pure offering” 3414
—such as the ascription of glory, and blessing, and praise, and hymns. Now, inasmuch as all these things are also found amongst you, and the sign upon the forehead, 3415
and the sacraments of the church, and the offerings of the pure sacrifice, you ought now to burst forth, and declare that the Spirit of the Creator prophesied of your Christ.

Ezek. ix. 4. The ms. which T. used seems to have agreed with the versions of Theodotion and Aquila mentioned thus by Origen (Selecta in Ezek.): ὁ δὲ ᾽Ακύλας καὶ Θεοδοτίων φασι. Σημείωσις τοῦ Θαῦ ἐπὶ τὰ μέτωπα, κ.τ.λ. Origen, in his own remarks, refers to the sign of the cross, as indicated by this letter. Ed. Bened. (by Migne), iii. 802.